Plug connections and plug connectors for use in a high-voltage on-board electrical system are known. For example, German patent applications DE 10 2015 104 377.7 and DE 10 2015 114 080.2 describe an electrical plug connector that is suitable for use in a high-voltage on-board electrical system. The electrical connector has a contact part with a sleeve that forms a receiving space in which a plug-in contact is guided in a direction of insertion. A contact spring is attached in the interior of the sleeve and is adapted to be urged by a displaceable locking bolt in the direction of the receiving space for the plug-in contact. The electrical plug connector equipped with this contact part facilitates insertion and withdrawal of the plug-in contact.
German patent document DE 20 2010 018 115 U1 discloses a plug connector in which a plug and a socket are locked together by a locking slide that can be pushed to the socket transversely to a plugging direction of the plug. However, the plug suffers from various drawbacks. For example, improved resistance to vibration would be desirable.